The Ladder of Divine Light is the ladder that can carry an extremely rich symbolism without ceasing to be perfectly coherent. It gives plastic expression to the break through the planes necessitated by the passage from one mode of being to another, by placing us at the cosmological point where communication between Heaven, Earth, and hell becomes possible. That is why the stairway and the ladder play so considerable a part in the rites and myths of initiation, as well as in the funerary rituals, not to mention the rites of royal or sacerdotal enthronement or those of marriage. But we also know that the symbolism of climbing-up and of stairs recurs often enough in psychoanalytic literature, and indication that it belongs to the archaic content of the human psyche and is not a “historical” creation, not an innovation dating from a certain historical moment (say, from ancient Egypt or Vedic India, etc. ).
The ideas of sanctification, of death, love, and deliverance are all involved in the symbolism of stairs. Indeed each of these modes of being represents a cessation of the profane human condition; that is, a breaking of the ontological plane. Through love, and death, sanctity and metaphysical knowledge, man passes–as it is said in the Brihadaranyaka Upanishad, from the “unreal to the reality.”
–Mircea Eliade from NOSTALGIA FOR PARADISE: symbolism of the center and the ritual approach to immortality, Ascent: